Drying racks are typically used in the printing arts as a means of inexpensively drying flat materials in a minimum of space. This is particularly the case with the drying of small quantities of materials to avoid the high installation and energy costs associated with the use of gas and electric dryers. For example, drying racks are extensively used in the screen printing business for the drying of small quantity jobs, as well as those jobs which require longer drying times and/or precise color registration attributable to room temperature drying conditions. Moreover, an increasing number of drying racks are being used for drying very large sheets of paper, boards, plastics, circuit boards, glass sheets, metals, woods, hardboards, and the like.
Drying racks have remained substantially unchanged over the years and typically comprise a metal frame chassis which supports up to 50 metal wire shelves or trays. The shelves are formed from crisscrossed metal wires and supported by, and hinged with counterbalancing springs to, a vertical metal frame to allow for pivoting of the shelves between horizontal and inclined positions. Under weight loads, the shelves are maintained in level alignment and prevented from touching one another, particularly on the side of the shelves away from the vertical support frame, by the use of spacers between the shelves. As illustrated in the Advance Process Supply Company's 1982 catalog, the spacers (or bumpers as they are referred to in the catalog) generally comprise 1 inch wide round edge metal bar stock formed into cylindrical shapes and welded to the outside corners of the metal shelves in such a way that they contact the spacers on the adjacent upper and lower shelves to maintain a preset distance between the shelves and ensure that the shelf remains level when loaded with a material to be dried.
U.S. Pat. No. 2,950,541 also describes a drying rack and a spacer therefor, which it terms a corner foot. The corner foot is for use on each shelf of a multiple shelf drying rack having a plurality of pivotal shelves positionable in a horizontal position or in an upwardly inclined position and reportedly allows for the shelves in the inclined position to be spaced a smaller distance apart than the shelves in the horizontal position. The corner foot comprises a generally three-sided stiffly yieldable body member which is relatively thick with respect to the shelf and which has parallel upper and lower surfaces and a generally triangular slot extending from one side thereinto intermediate and substantially parallel to the surfaces for receiving a shelf corner and a leg portion depending from the lower surface of the body and terminating in a bottom surface which is generally parallel to the upper body surface. The leg portion extends along one side of the body member corresponding to the front edge of the shelf, with the width of the leg being substantially narrower than the lower body surface so that the leg is supported on the upper surface of the next lower foot when the shelves are horizontal, and the upper surface of the foot is supported against the lower surface of the next upper corner foot when the shelves are inclined upwardly, with the depending leg of the latter overhanging the forward edge of the former so that the shelves are spaced from each other. The corner foot is made of a stiff, but yieldable material, such as hard rubber, so that it may be forced over the corner edge of the shelf with the shelf frame wire being retained in the enlarged slot portion of the corner foot so that the foot is securely retained on the shelf.
While drying racks and spacers have been utilized for quite a few years, there remains a need for a simple spacer that can be easily applied by the user to a drying rack shelf to maintain any desirable spacing of drying rack shelves, maintain that desirable spacing at any pivotal angle of the drying rack shelves, and provide for additional support for drying rack shelves under the weight of heavier loads, without reducing the shelf area available for supporting the items to be dried on the drying rack shelves.